amdgpu: Add wrappers for AMDGPU_VM IOCTL.

v2:
Rename wrappers to match the IOCTL naming, fix
identation and fix make check error.

Signed-off-by: Andrey Grodzovsky <Andrey.Grodzovsky@amd.com>
Reviewed-by: Christian König <christian.koenig@amd.com>